In 1878 Marignac, having subjected Mosander’s erbia, obtained from gadolinite, to a careful examination, announced the presence of a new element, ytterbium; this discovery was confirmed by Nilson, who in the following year discovered another element, scandium, in Marignac’s ytterbia.

The other members of the group closely resemble it, and amongst them are erbia, terbia, ytterbia, scandia, &c.